Queen's letter details Charles and Andrew's excitement over new born

A deeply personal letter written by Queen Elizabeth II shortly after the birth of Prince Edward has resurfaced, revealing the late monarch's life as a young mother and the happiness that filled the royal household in 1964.

Penned from Buckingham Palace on April 1 that year, the handwritten letter was sent to the Queen's close friend, concert pianist Marion Stein, Countess of Harewood, just weeks after Edward's arrival.

In the warm correspondence, Elizabeth described her youngest son as "flourishing" and revealed how delighted the family was to once again have a baby in the nursery.

"There is a great joy in having a baby in the nursery again," the Queen wrote, adding that her older children - Prince Charles, Princess Anne and Prince Andrew were all "thrilled" with their new baby brother.

The two-page letter, which is expected to fetch around £1,000 at auction, showcases a side of the monarch rarely seen by the public. 

Far from official duties and state affairs, it captures a mother sharing family updates with a trusted friend.

The Queen also displayed her trademark humour in the note. Apologising for taking time to respond, she blamed a "very large pile of correspondence" before joking about Britain's cold spring weather while referencing Stein's recent trip to Russia.

"It must have still been extremely cold there," she wrote, "though this country seems to be doing its best to copy it just now."

The letter was addressed to Marion Stein, a celebrated Austrian-born pianist whose friendship with the Queen lasted decades. 

Stein's remarkable life saw her rise to prominence in British cultural circles, first through her marriage to George Lascelles, the 7th Earl of Harewood, and later to Liberal Party leader Jeremy Thorpe.

Their enduring friendship was formally recognised in 2008 when the Queen appointed Stein a Commander of the Order of the British Empire for her services to music.

Auction specialist Richard Davie described the correspondence as a rare and intimate insight into Elizabeth's private world.

"It shows the Queen not as a monarch, but as a devoted mother," he said. "Her affectionate observations, humour and warmth make her feel remarkably approachable."

The discovery comes shortly after another letter from the same year emerged, written by the Queen to Sister Helen Rowe, affectionately known as "Rowie," who helped care for her throughout all four pregnancies.

In that note, written when Edward was five months old, Elizabeth proudly described her youngest child as "wonderful" and "good as gold," revealing that he weighed an impressive 15lb 12oz.

"He smiles and giggles at everyone, and makes everyone happy!" she wrote.

The letter also offered an update on Prince Charles, then 15, who was recovering from pneumonia after a camping trip. 

While relieved by his progress, the Queen admitted he remained "very frail as yet."